WO2007062576A1

WO2007062576A1 - Method, system and base station for multimedia broadcast/multicast service

Info

Publication number: WO2007062576A1
Application number: PCT/CN2006/003038
Authority: WO
Inventors: Rongqiang Li
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2005-11-30
Filing date: 2006-11-13
Publication date: 2007-06-07
Also published as: EP1879403A4; EP1879403B1; CN101160982A; CN1870468A; EP1879403A1; CN101160982B; EP1879403B9

Abstract

A method for realizing multimedia broadcast/multicast service MBMS comprises: the base station adjusts the downlink modulation mode according to the uplink indication information fed back by terminals, and provides MBMS service to terminal according to the adjusted downlink modulation mode. Moreover, a system and a base station for MBMS are provided, the system comprises base station and terminals, and the base station comprises a receiving unit, a transmitting unit and a adjusting unit. The present invention can save power resources and ensure the MBMS QoS in the mean time.

Description

Method and system for implementing multi-cast broadcast multicast service

The present invention relates to the field of wireless communications, and in particular, to a multimedia broadcast multicast service.

(Multimedia Broadcast I Multicast Service, MBMS) implementation method, an MBMS system and a base station. Background of the invention

Broadcast and multicast are the means of transmitting data from one data source to multiple users. In traditional mobile networks, cell broadcast services allow low bit rate data to be sent to all users over a cell shared broadcast channel. Nowadays, the demand for mobile communication is no longer satisfied with the telephone and message services. With the rapid development of the Internet, a large number of multimedia services have emerged. Some of the application services, multiple users can receive the same data at the same time, such as video on demand, TV. Broadcasting, video conferencing, online education, interactive games, and more. Compared with general data, these mobile multimedia services are characterized by large data volume, long duration, and delay sensitivity. In order to achieve the most efficient use of mobile network resources, WCDMA/GSM Global Standards Organization 3GPP. proposes multimedia broadcast multicast service MBMS, which refers to a point-to-multipoint service in which a data source sends data to multiple users, and realizes network resource sharing, including Mobile core network and access network resource sharing, especially air interface resources. MBMS defined by 3GPP can not only realize plain text low-rate message class multicast and broadcast, but also realize high-speed multimedia service multicast and broadcast, which is in line with the trend of future mobile data development.

The current MBMS service is based on the downlink assisted public control physical channel (S-CCPCH) for air interface wireless propagation. Referring to Figure 1, the MBMS service is carried on the S-CCPCH channel, and the whole cell coverage is enabled, so that the MBMS users in the whole cell can Receive MBMS service. The MBMS based on the downlink S-CCPCH configures the corresponding transmission format according to the transmission rate requirement of the MBMS service, and selects an appropriate downlink spreading factor to support different rate services, such as fixed or Variable rate broadcast service, and one S-CCPCH allows multiplexing of multiple MBMS services. The range of spreading factors supported by S-CCPCH is from 256 to 4. When the spreading factor is equal to 4, the maximum number of information supported per frame is 12720 bits, which is equivalent to the maximum rate supported by a single S-CCPCH of air interface up to 1.272 Mbps. According to the code rate of 1/4, the MBMS service rate of 318 Kbps can be supported. In addition, the downlink S-CCPCH-based MBMS adopts open-loop power control, and needs to determine the downlink transmit power of the S-CCPCH according to the farthest distance and the worst propagation environment covered by the cell edge, and the received signal-to-noise ratio requirement of the MBMS service. The MBMS service can be clicked on with a certain access probability even when the cell user is at the edge.

It can be seen that the main drawback of the MBMS based on the downlink S-CCPCH is: Since the MBMS service is required to achieve full coverage in the cell, regardless of whether the MBMS user is currently close to the base station or not, the power needs to be transmitted according to the coverage requirement of the cell edge, which is easy to cause power. Waste; and, because closed-loop power control is not used, in order to combat the poor channel conditions that MBMS users may encounter, to obtain certain user reception satisfaction, it is necessary to transmit high power. When the number of MBMS users is relatively small, power resources Waste is more serious.

In addition, MBMS based on downlink S-CCPCH has the following disadvantages:

After the MBMS service carried on the S-CCPCH is sent to the MBMS user, the base station cannot quickly obtain the receiving satisfaction of the MBMS user, so the MBMS user satisfaction cannot be quickly adjusted through the downlink transmission control, thereby resulting in the comparison of the service guarantee of the MBMS service. Poor

Since the supported MBMS service rate is relatively limited, considering the need to achieve coverage of the whole cell, the rate of the MBMS service will be much less than 1 Mbps. Therefore, for the MBMS service with high quality multimedia requirements in the future, the MBS based on the downlink S-CCPCH is transmitted. There may be some bottlenecks in the rate;

It is not flexible enough to provide service quality and downlink resource utilization. It does not bring the greatest value to operators. For example, if operators use MBMS based on S-CCPCH, they must deploy according to service planning and implement S in the corresponding community. - Full coverage of CCPCH, according to a certain community The code resource and the power resource are allocated, and the resources are relatively poor in resource sharing with the downlink channels such as other downlink dedicated channels, and the S-CCPCH has no composite retransmission mechanism, so the flexibility of power reduction is obtained by retransmission delay. It is also poor, unable to provide a compromise between the quality of service and the downstream resources, and cannot provide diversification of service quality. Summary of the invention

In view of this, the main purpose of the present invention is to provide a method, system, and base station for implementing a multimedia broadcast multicast service, which reduces power resource waste.

To achieve the above, the method for implementing the multimedia broadcast multicast service provided by the present invention is as follows: The base station adjusts the downlink modulation mode according to the indication information of the terminal uplink feedback, and issues the MBMS service to the terminal according to the adjusted downlink modulation mode.

The base station issues an MBMS service to the terminal through a downlink shared channel.

The downlink shared channel includes a downlink shared signaling channel and a downlink shared data channel; the transmitting, by the base station, the MBMS service to the terminal by using the downlink shared channel includes:

The MBMS service data bearer is sent to the terminal on the downlink shared data channel, and the accompanying demodulation signaling of the downlink shared data channel is carried on the downlink shared signaling channel and sent to the terminal.

The method further includes allocating the same downlink shared signaling channel identity to all MBMS users.

The downlink shared data channel is a high speed physical downlink shared channel HS-PDSCH; and the downlink shared signaling channel is a high speed shared control channel HS-SCCH.

The terminal feeds back indication information to the base station through an uplink feedback channel.

The uplink feedback channel is a high speed dedicated physical control channel HS-DPCCH.

The downlink modulation mode includes a transmit power, the indication information of the uplink feedback includes a data receiving performance, and the adjusting the transmit power according to the data receiving performance includes: determining a user actual satisfaction according to the data receiving performance fed back by the terminal, according to the actual user satisfaction The transmission power correction amount is determined, and the transmission power is adjusted according to the determined transmission power correction amount. The data receiving performance includes a data correct receiving indication and a receiving satisfaction indication. The actual satisfaction of the user is a ratio of the number of correctly received indication data or the number of satisfactory indications to the total number of indications.

The determining the amount of transmission power according to the actual satisfaction of the user includes: setting the target satisfaction degree, the upward adjustment step amount, and the downward adjustment step amount in advance, and when the actual user satisfaction is greater than the target satisfaction degree, the previous correction amount and the downward adjustment step are performed. The difference between the distances is taken as the current correction amount; otherwise, the sum of the previous correction amount and the upper adjustment step amount is taken as the current positive amount, wherein the initial value of the up-step amount and the down-step amount is the order.

The adjusting the transmit power according to the determined transmit power correction amount includes: using a sum of the current transmit power and the transmit power correction amount as the adjusted transmit power.

The downlink modulation mode includes a transmit power, and the indication information of the uplink feedback includes a channel quality indicator, and the adjusting the transmit power according to the channel quality indicator includes: selecting a channel quality indicator that satisfies a user target satisfaction according to a channel quality indicator fed back by the terminal And determining a transmit power correction amount according to the selected channel quality indicator, and adjusting the transmit power according to the determined transmit power correction amount.

The determining the transmit power correction amount according to the selected channel quality indicator comprises: using a difference between the channel quality indicator corresponding to the fixed transmission format and the channel quality indicator capable of satisfying the user target satisfaction as the transmit power correction amount.

The downlink modulation mode includes a transmission format and a transmission power, and the indication information of the uplink feedback includes a channel quality indicator, and the adjusting the transmission format and the transmission power according to the channel quality indicator includes: selecting, according to a channel quality indication fed back by the terminal, the user target The channel quality indicator of satisfaction, and adjusts the transmission format and transmission power according to the selected channel quality indication.

Determining, according to a channel quality indication fed back by the terminal, a channel capable of satisfying user target satisfaction The quality indicator includes: pre-setting user target satisfaction, the base station will arrange the channel quality indicators fed back by each terminal in descending order of value, and select the index number as the product target satisfaction and the number of all channel quality indicators. The channel quality indicator of the value is indicated as a channel quality that satisfies the user's target satisfaction.

The present invention also provides a multimedia broadcast multicast service MBMS system, the system comprising: a base station and at least one terminal, wherein the terminal is configured to receive an MBMS service from the base station, and feed back indication information to the base station; The indication information fed back by the terminal adjusts the downlink modulation mode according to the received indication information, and issues the MBMS service to the terminal according to the adjusted downlink modulation mode.

The base station includes: a receiving unit, a sending unit, and an adjusting unit, where the receiving unit is configured to receive the indication information fed back by the terminal, and send the received indication information to the adjusting unit, where the adjusting unit is configured to receive the receiving unit The indication information is adjusted according to the received indication information, and the adjusted downlink modulation mode is sent to the sending unit, and the sending unit is configured to receive the downlink modulation mode from the adjusting unit, according to the received downlink modulation mode. The delivered MBMS service is modulated, and the modulated MBMS service is sent to the terminal.

The downlink modulation mode includes a transmit power, and the indication information includes a data receiving performance, and the adjusting unit further includes: a first transmit power adjustment module, configured to determine a user actual satisfaction according to the received data receiving performance, according to the actual user Satisfaction determines the transmit power correction amount, and adjusts the transmit power according to the transmit power correction amount.

The downlink modulation mode includes a transmit power, the indication information includes a channel quality indicator, and the adjusting unit further includes: a second transmit power adjustment module, configured to select, according to the received channel quality indicator, a channel that satisfies a user target satisfaction degree The quality indicator determines the transmit power correction amount according to the selected channel quality indicator, and adjusts the transmit power according to the transmit power correction amount.

The downlink modulation mode includes a transmission format and a transmission power, the indication information includes a channel quality indicator, and the adjustment unit further includes: a modulation mode adjustment module, configured to receive the received message according to the The channel quality indicator selects a channel quality indicator that satisfies the user's target satisfaction, and adjusts the transmission format and the transmission power according to the selected channel quality indicator.

In addition, the present invention further provides a base station, the base station includes: a receiving unit, a sending unit, and an adjusting unit, where the receiving unit is configured to receive the indication information fed back by the terminal, and send the received indication information to the adjusting unit; The adjusting unit is configured to receive the indication information from the receiving unit, adjust the downlink modulation mode according to the received indication information, and send the adjusted downlink modulation mode to the sending unit, where the sending unit is configured to receive the downlink from the adjusting unit The modulation mode modulates the delivered MBMS service of the multimedia broadcast multicast service according to the received downlink modulation mode, and sends the modulated BMS service to the terminal.

The downlink modulation mode includes the transmit power, the indication information includes the data receiving performance, and the adjusting unit further includes: a first transmit power adjustment module, configured to determine a user actual satisfaction according to the received data receiving performance, according to the user The actual satisfaction determines the transmission power correction amount, and adjusts the transmission power according to the transmission power correction amount.

The downlink modulation mode includes a transmission format and a transmission power, and the indication information includes a channel quality indicator, and the adjusting unit further includes: a modulation mode adjustment module, configured to select, according to the received channel quality indicator, a satisfaction that satisfies a user target satisfaction. The channel quality indication, and the transmission format and transmission power are adjusted according to the selected channel quality indicator.

It can be seen that the present invention has the following beneficial effects:

1) The MBMS user can feed the indication information to the base station through the uplink feedback channel, and the base station can adjust the required transmission power or transmission format according to the information fed back by the MBMS user in real time, and since the probability that the MBMS user is not at the cell edge is large in many cases, Therefore the base station does not need to The fixed power is transmitted according to the coverage of the cell edge, which saves the actual power of the downlink providing MBMS service, so that the power resources are effectively utilized.

2) The base station can perform power control according to the channel quality condition fed back by the user in real time, and the open loop power control of the MBMS based on the downlink S-CCPCH can only be transmitted according to the worst channel condition, so the solution of the present invention has higher Power control efficiency.

3) The base station can estimate the current satisfaction of the MBMS user through the data receiving performance fed back by each user, and perform real-time intervention according to the operator's satisfaction configuration strategy, thereby obtaining better user satisfaction guarantee and providing different MBMS for the operator. Differentiated services for the business provide a way.

4) The present invention can also adjust the downlink transmit power through a certain composite automatic retransmission and scheduling period, and achieve a certain service quality requirement, and the MBMS based on the downlink S-CCPCH needs to adopt a relatively large downlink transmit power, so that the data is Better demodulation performance is sent at one time.

5) The MBMS based on the downlink shared channel is an extension of the data transmission of the downlink shared channel of a single user. In the case of consuming almost the same downlink resources, the same data transmission can be provided for more users, which is "cheap," The business provides a way.

6) The MBMS based on the downlink shared channel can provide a very high MBMS service rate. In the Release 6.0 version of the WCDMA standard, the peak rate of the service theory based on the downlink shared channel is much larger than the peak rate of the S-CCPCH.

7) The downlink resource sharing can be implemented by the MBMS based on the downlink shared channel. If no MBMS user applies for the MBMS service, the cell can be borrowed, and the downlink resource of the MBMS service is not returned until the MBMS user initiates the service request. And when the channel quality is good, the redundant downlink resources of the MBMS service can be shared with other users except the MBMS user, or when the channel quality is poor, the MBMS user can "borrow," the downlink resources of other users. The downlink shared channel can fully share downlink resources, which provides a possibility for providing high-speed downlink MBMS services. BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of an MBMS based on a downlink assisted public control physical channel in the prior art. 2 is a schematic structural view of an MBMS system in the present invention.

FIG. 3 is a schematic structural diagram of a base station in the present invention.

FIG. 4 is a flowchart of a method for implementing an MBMS in a variable transmission format according to Embodiment 1 of the present invention. FIG. 5 is a flowchart of determining channel quality according to feedback from an MBMS user according to Embodiment 1 of the present invention;

Flowchart of MBMS downlink shared data channel transmission format and transmission power.

6 is a data reception performance correction according to MBMS user feedback in the first embodiment of the present invention.

Flowchart of MBMS downlink shared data channel transmit power.

FIG. 7 is a flowchart of a method for implementing MBMS in a fixed transmission format according to Embodiment 2 of the present invention. FIG. 8 is a flowchart of channel quality indication correction according to MBMS user feedback according to Embodiment 2 of the present invention;

Flowchart of MBMS downlink shared data channel transmit power. Mode for carrying out the invention

The basic idea of the MBMS method provided by the present invention is that the base station adjusts the downlink modulation mode according to the indication information of the uplink feedback of the terminal, and issues the MBMS service to the terminal according to the adjusted downlink modulation mode.

The base station can carry the MBMS service to the downlink shared channel for air interface wireless propagation, and the terminal can feed the indication information to the base station through the uplink feedback channel. The downlink shared channel is divided into a downlink shared signaling channel and a downlink shared data channel, the downlink shared data channel is used to carry the MBMS service, and the downlink shared signaling channel provides demodulation signaling for the downlink shared data channel accompanied by the terminal demodulation, and In order for all MBMS users to share the downlink shared signaling channel, all MBMS users are assigned the same downlink shared signaling channel identifier to achieve point-to-multipoint propagation. Each MBMS user feeds back indication information such as channel quality indication and data reception performance to the base station through the terminal according to its own channel quality condition and received data performance; the base station adjusts modulation such as downlink transmission format and transmission power according to the received indication information. The method is to save power resources, control and improve the service quality of the MBMS service in real time, improve the bearer capability of the MBMS service based on the downlink shared channel, and the MBMS user demodulates the received data by using a composite automatic retransmission technology. Business quality requirements.

According to the method provided by the present invention, the present invention further provides a multimedia broadcast multicast service system. As shown in FIG. 2, the MBMS system includes: a base station and a terminal, where the terminal is configured to receive an MBMS service from the base station, And transmitting the indication information to the base station, and the base station is configured to receive the indication information fed back by the terminal, adjust the downlink modulation mode according to the received indication information, and issue the MBMS service to the terminal according to the adjusted downlink modulation mode.

Referring to FIG. 3, the base station includes at least a receiving unit, a sending unit, and an adjusting unit, where the receiving unit is configured to receive indication information fed back by the terminal, and send the received indication information to the adjusting unit; Receiving the indication information from the receiving unit, adjusting the downlink modulation mode according to the received indication information, and transmitting the adjusted downlink modulation mode to the sending unit, and the sending unit, configured to receive the downlink modulation mode from the adjusting unit, according to The received downlink modulation mode modulates the delivered MBMS service of the multimedia broadcast multicast service, and sends the modulated MBMS service to the terminal.

The adjusting unit of the base station may further include a first transmit power adjustment module, a second transmit power adjustment module, a modulation mode adjustment module, and the like. The first transmit power adjustment module is configured to determine a user's actual satisfaction according to the received number of received performances, determine a transmit power correction amount according to the actual user satisfaction, and adjust the transmit power according to the transmit power correction amount; And a second transmit power adjustment module, configured to select, according to the received channel quality indicator, a channel quality indicator that satisfies the user target satisfaction, determine a transmit power correction amount according to the selected channel quality indicator, and adjust the transmit power according to the transmit power correction amount. The modulation mode adjustment module is configured to select a channel quality indicator that satisfies the user target satisfaction according to the received channel quality indicator, and adjust the transmission format and the transmission power according to the selected channel quality indicator. The specific adjustment process for each of the above adjustment modules will be fully embodied in the following embodiments.

The present invention is applicable to all wireless communication systems based on downlink shared channels. In order to make the objects, technical solutions and advantages of the present invention more clear, the following high-speed downlink packets are defined by the WCDMA standard. The High Speed Downlink Packet Access (HSDPA) technology is taken as an example to illustrate the implementation process of the present invention.

As a high-speed downlink packet access technology, HSDPA was introduced into the 3GPP Release 5 version in 2002. The main features of HSDPA are: Using 2ms short frames, using composite automatic retransmission (HARQ) and adaptive modulation coding at the physical layer ( AMC technology introduces 16QAM high-order modulation to improve spectrum utilization, and realizes shared channel scheduling of each user by code division and time division. The HARQ technology adopts the SAW protocol. After the base station is required to send data to the user, the user needs to feedback whether the data has been correctly received by the response ^^/ \3⁄4C, so that the base station determines whether it is necessary to retransmit the data. HSDPA adds two physical channels in the downlink: one is the High Speed Physical Downlink Shared Channel (HS-PDSCH), which is used to carry the user's data information; the other is the high speed shared control channel (High Speed Shared Control) Channel, HS-SCCH), used to carry the signaling required to demodulate the data channel HS-PDSCH, and advances the data frame HS-PDSCH channel by 2 slots in time. HSDPA adds a physical channel, that is, High Speed Dedicated Physical Control Channel (HS-DPCCH), which is used to carry the received performance information of the downlink HS-PDSCH data frame ^ ^ / C and downlink The channel quality indicator CQ _L user indicates the transmission format allowed by the base station under a certain HS-PDSCH transmission power according to the currently received channel quality, including the transmission block size, the modulation mode, the number of HS-PDSCH channel codes, and the like. Information, the base station instructs the downlink data transmission format according to the received channel quality indication CQI.

To ensure the normal operation of the MBMS service, the downlink shared signaling channel resource needs to be allocated for the MBMS service, and the downlink shared signaling channel provides demodulation signaling for the downlink shared data channel that is demodulated by each MBMS user. MBMS users can share the downlink shared signaling channel to achieve point-to-multipoint broadcast. All MBMS users are assigned the same downlink shared signaling channel identifier, and provide downlink for MBMS services in order to improve the reliability of downlink shared channel signaling. The channel transmit power of the signaling will be controlled based on the channel reception quality of the MBMS user, for example, root The transmit power of the MBMS downlink shared signaling channel is determined according to the worst channel reception quality of the MBMS user.

If the HSDPA technology is adopted, the HS-SCCH can provide signaling for the demodulation accompanying data channel, and all MBMS users are assigned the same user identification number, which is used as the group network identification number G-R TI of the MBMS, which is equivalent to the standard protocol. The network identifier ¹ H - RNTI, used to distinguish users from other services and individual business needs. All users belonging to the group network identification number G - R TI are assigned the same downlink HS - SCCH channel code and scrambling code, so that all MBMS users can listen to the downlink shared signaling channel in real time and determine whether there is a need to receive MBMS business.

The present invention will be further described in detail below with reference to the accompanying drawings and two specific embodiments, one of which is an MBMS implementation method of a variable transmission format, and the other is an MBMS implementation method of a fixed transmission format.

Embodiment 1

The variable transmission format means that the transmission format of the MBMS downlink shared data channel changes with the channel shield indication fed back by the terminal. Referring to FIG. 4, the MBMS implementation method of the variable transmission format mainly includes the following steps:

Step 401: Determine a transmission format and a transmission power of the MBMS downlink shared data channel according to the channel quality indication fed back by the terminal.

Each MBMS user periodically feeds back the channel quality indicator to the base station through the terminal according to its own channel quality condition, such as HSDPA high-speed dedicated physical control channel HS-DPCCH feedback, and the base station will feedback in real time according to each MBMS user. The channel quality indicator determines the transmission format and transmission power of the MBMS downlink shared data channel.

Step 402: After determining the transmission format and the transmission power, the MBMS service is carried on the downlink shared channel and sent to the MBMS user according to the determined transmission format and the transmission power.

The MBMS service data is carried on a downlink shared data channel (such as the high-speed physical downlink shared channel HS-PDSCH of HSDPA), and the MBMS demodulates the signaling required for the data channel. It is carried on a downlink shared signaling channel (such as HSDPA's High Speed Shared Control Channel HS - SCCH). Step 403: The terminal monitors the downlink shared signaling channel in real time (such as a high-speed shared control channel).

HS - SCCH ), determines whether there is currently data to be received, and if so, receives the MBMS service on the corresponding downlink shared channel.

Step 404: Each MBMS terminal feeds back data reception performance to the base station through an uplink feedback channel (such as HSDPA high-speed dedicated physical control channel HS-DPCCH) according to the currently received data quality.

Step 405: The base station adjusts the transmit power of the MBMS downlink shared data channel according to the data receiving performance fed back by the terminal.

After determining the transmit power of the MBMS downlink shared data channel according to the channel quality indication fed back by the MBMS user, the base station corrects the transmit power by using the data reception performance fed back by the MBMS user, and returns the corrected transmit power as the determined transmit power. Step 402 is performed, that is, the MBMS service is sent according to the modified transmit power to better adapt to the user's needs. The initial value of the power correction amount is 0. When the MBMS service is sent for the first time, the transmission power determined in step 401 is directly performed, and once the MBMS user is online, the correction amount according to the real-time evaluation of the data reception performance according to the feedback of the MBMS user is continuously performed. The transmit power is corrected, and then the MBMS service is sent according to the corrected transmit power. The power correction period is generally a period in which the MBMS user feeds back the data reception performance.

During the execution of the above steps, if the base station receives the current channel quality indication, step 401 is restarted according to the current channel quality indicator.

Referring to FIG. 5, the specific operation process of step 401 includes:

Step 501: The base station selects a channel quality indicator that satisfies the satisfaction degree of the MBMS user target according to the channel quality indication fed back by the terminal.

Assume that the current number of online MBMS users is N, and the channel quality indicators received by the base station are ί3⁄4Α, CQI ₂ , ..., CQI _{N respectively} , and the operator's predetermined MBMS user target satisfaction is ^arge H. CQI ₂ CQI _{N is} sorted in descending order by value

Sort_Descending{CQI ₁ , CQI ₂ , . . . , CQI _N }, and select the channel quality indicator corresponding to the index number LNx argd J as the channel quality indicator that can currently satisfy the MBMS user target satisfaction degree.

, where L" means rounding down.

Other options may be adopted for the selection of (not limited to the above). Step 502: The base station determines the transmission format and transmission power of the MBMS downlink shared data channel according to the selected channel quality indication.

The specific operation of step 401 can be completed by the modulation mode adjustment module.

Specifically, how to determine the transmission format and the transmission power by the channel quality indicator belongs to the existing standard protocol content, and details are not described herein again. For MBMS services with a certain rate and delay requirement, the base station can satisfy the requirement by allocating the number of downlink schedulable data transmissions.

Referring to Figure 6, the specific operation process of step 405 includes:

Step 601: The base station determines the actual satisfaction of the MBMS user according to the data receiving performance fed back by the terminal.

Assume that the current number of online MBMS users is N, and the data reception performance received by the base station is

^, ^2 , where · , = (1,···,Λ , can indicate whether the data is correctly received

ACKINACK, or whether to receive a satisfactory indication ^ etc. to reflect the reception performance information,

Ν

R † _ _ =1

Count the ratio of the number of correctly received indications to the total number of indications N or

The number of satisfaction indications is the ratio of the total number of indications Κ ^ί)

And as the actual satisfaction of MBMS users.

Step 602: The base station determines the actual satisfaction of the MBMS user to determine the transmit power correction amount of the MBMS downlink shared data channel. Correction amount ^Δ (the value of 0 is determined by the actual satisfaction of the MBMS user and the satisfaction of the operator's predetermined MBMS user target ⁷¹ ^ - ^ ', ^Δ (the initial value of 0 is 0, if UO^a^H, then one is given The amount of stepwise adjustment of the upward adjustment is Up-Po Cao-Step determines Δ(0, A(t) = A(t - T) + Up_ Power- Step. If R _sat (t) > arg et - R _sat , then according to a given downward adjustment steps ^ massive ^down - ^power - ^Ste P determined ^{Δ (, a (t) =} a (t - T) - down a a power step, wherein 7.1 to power modification period, Generally, the terminal feeds back the period of data reception performance.

Other suitable schemes may be adopted for the determination of the positive quantity, and are not limited to the above one.

Step 603: The base station corrects the transmit power of the MBMS downlink shared data channel according to the determined transmit power correction amount.

The correction amount ^{Δ is} obtained from step 602 (after 0, the base station uses ^Δ (0 corrects the current transmission power, and the corrected transmission power is:) HO + A(t). Then, the base station determines the corrected transmission power as the determined Transmit power, return to step 402.

The specific operation of step 405 can be performed by the first transmit power adjustment module.

Embodiment 2

The solid transport format means that the transport format of the MBMS downlink shared data channel is determined by the transmission rate requirement of the MBMS service and does not change with the channel quality indication fed back by the MBMS user. Referring to Figure 7, the MBMS implementation method of the fixed transmission format mainly includes the following steps:

Step 701: The base station determines, according to the transmission rate requirement of the MBMS service, the transmission format of the MBMS downlink shared data channel, so that the channel quality indication corresponding to the transmission format is ^, and then the base station determines the transmission power W of the MBMS downlink shared data channel according to the determination.

Specifically, how to determine the transmit power according to the channel quality indicator belongs to the existing standard protocol content, and details are not described herein again.

Step 702: The base station sends the MBMS service on the downlink shared channel to the MBMS user according to the determined transmission format and the transmit power. The MBMS service data is carried on a downlink shared data channel (such as HS-PDSCH), and the signaling required for the MBMS demodulation accompanying the data channel is carried on a downlink shared signaling channel (such as HS-SCCH).

Step 703: The terminal monitors the downlink shared signaling channel (such as HS-SCCH) in real time to determine whether there is currently data to be received, and if yes, receives the MBMS service on the corresponding downlink shared channel.

Step 704: The terminal feeds back data reception performance to the base station by using an uplink feedback channel (such as HS-DPCCH) according to the currently received data quality.

Step 705: The base station adjusts the transmit power of the MBMS downlink shared data channel according to the data receiving performance fed back by the terminal.

After the base station determines the transmit power of the MBMS downlink shared data channel according to step 701, the base station uses the data received performance of the MBMS user feedback to correct the transmit power, and uses the corrected transmit power as the determined transmit power, and returns to step 702. The transmission of the DBMS service is performed according to the corrected transmission power to better adapt to the user's needs. The initial value of the power correction amount is 0. When the MBMS service is sent for the first time, the transmission power determined in step 701 is directly performed, and once the multicast broadcast user is online, the correction amount is evaluated in real time according to the data reception performance according to the feedback of the MBMS user. The transmission power is continuously corrected, and then the MBMS service is transmitted according to the corrected transmission power. The power correction period is generally a period in which the terminal feedbacks the data reception performance.

The specific operation process of step 705 is the same as step 405, and details are not described herein again.

In addition, the base station may further modify the transmit power of the MBMS downlink shared data channel according to the channel quality indication fed back by the terminal, and the process may be performed by the second transmit power adjustment module, as shown in FIG. 8 , according to the channel quality fed back by the terminal. The process of indicating the modification of the transmit power of the MBMS downlink shared data channel specifically includes the following steps:

Step 801: The base station selects a channel quality indicator that satisfies the target satisfaction of the MBMS user according to the channel quality indication fed back by the terminal. For the selection of <3⁄4/' «, refer to step ₅₀₁ , and details are not described here. Step 802: The base station determines the transmit power correction amount ^Δ according to the selected channel quality indicator ^^ '^) and the channel quality indicator ^C ^^ corresponding to the fixed transmission format. ( ⁰ , ^Δ . ( ^{0 = ί3⁄4} — ^Ce U ⁰ , ^Δ . ⁽ The initial value of 0 is 0.

Step 803: The base station corrects the amount ^A according to the determined transmit power. W corrects the current transmit power of the MBMS downlink shared channel, and the corrected transmit power is: 4 (0 = -.) + Δ. (0.

Then, the base station uses the corrected transmit power as the determined transmit power, and returns to the execution step.

702. Among them, ^Τ . The period for performing power correction according to the channel quality indication fed back by the MBMS user is generally the same as the period of the terminal feedback channel quality indication.

According to the channel quality indication and data reception performance corrected by the MBMS user, the transmission power is performed in parallel, and each correction is performed on the basis of the previous correction result.

It should be noted that, in the present invention, the method for adjusting the downlink modulation mode by the base station according to the indication information fed back by the terminal is not limited to the two embodiments described above. For example, the base station may only adjust the data reception performance based on the feedback of the terminal. The transmission power, or the transmission power is adjusted according to the channel quality indication fed back by the terminal, or the transmission format is adjusted according to the channel quality indication fed back by the terminal.

It can be seen that the solution provided by the present invention can adjust the modulation mode such as the transmission format or the transmission power in real time according to the indication information fed back by the user, and can effectively utilize the power resources while ensuring the MBMS service quality, and can realize the complete sharing of the downlink resources. It provides the possibility to provide high-speed downlink MBMS services.

The above-mentioned objects, technical solutions, and advantageous effects of the present invention are further described in detail. It is to be understood that the above description is not intended to limit the present invention, and is within the spirit and principles of the present invention. Any modifications, equivalent substitutions, improvements, etc., are intended to be included within the scope of the present invention.

Claims

Claim

A method for implementing a multimedia broadcast multicast service MBMS, the method includes the following steps: The base station adjusts a downlink modulation mode according to the indication information of the terminal uplink feedback, and issues an MBMS service to the terminal according to the adjusted downlink modulation mode.

2. The method according to claim 1, wherein the base station issues an MBMS service to the terminal through the downlink shared channel.

3. The method according to claim 2, wherein the downlink shared channel comprises a downlink shared signaling channel and a downlink shared data channel;

The transmitting, by the base station, the MBMS service to the terminal by using the downlink shared channel includes: transmitting, by the base station, the MBMS service data on the downlink shared data channel to the terminal, and carrying the accompanying demodulation signaling of the downlink shared data channel on the downlink shared signaling channel. Send to the terminal.

The method of claim 3, wherein the method further comprises: allocating the same downlink shared signaling channel identifier for all MBMS users.

The method according to claim 3 or 4, wherein the downlink shared data channel is a high speed physical downlink shared channel HS-PDSCH; and the downlink shared signaling channel is a high speed shared control channel HS-SCCH.

The method according to claim 1, wherein the terminal feeds the indication information to the base station through the uplink feedback channel.

The method according to claim 6, wherein the uplink feedback channel is a high speed dedicated physical control channel HS-DPCCH.

The method according to claim 1, wherein the downlink modulation mode includes transmit power, and the indication information of the uplink feedback includes data receiving performance,

The adjusting the transmit power according to the data receiving performance comprises: determining the actual user satisfaction according to the data receiving performance fed back by the terminal, determining the transmit power correction amount according to the actual user satisfaction, and adjusting the transmit power according to the determined transmit power correction amount.

The method according to claim 8, wherein the data receiving performance comprises a data correct receiving indication and a receiving satisfaction indication.

The method according to claim 9, wherein the actual satisfaction of the user is a ratio of the number of correctly received indication data or the number of satisfactory indications to the total number of indications.

11. The method according to claim 8, wherein the determining the transmit power correction amount according to the actual user satisfaction comprises:

The target satisfaction degree, the upward adjustment step amount and the downward adjustment step amount are set in advance. When the actual user satisfaction is greater than the target satisfaction degree, the difference between the previous correction amount and the downward adjustment step amount is used as the current correction amount; The sum of the primary correction amount and the upward adjustment step distance is used as the current correction amount, wherein the initial value of the upward adjustment step amount and the downward adjustment step amount is zero.

The method according to claim 8 or 11, wherein the adjusting the transmit power according to the determined transmit power correction amount comprises: using the sum of the current transmit power and the transmit power correction amount as the adjusted transmit power .

The method according to claim 1 or 8, wherein the downlink modulation mode includes a transmit power, and the indication information of the uplink feedback includes a channel quality indicator.

The adjusting the transmit power according to the channel quality indicator comprises: selecting a channel quality indicator capable of satisfying the user target satisfaction according to the channel quality indication fed back by the terminal, determining a transmit power correction amount according to the selected channel quality indicator, and determining the transmit power correction amount according to the determined Adjust the transmit power.

The method according to claim 13, wherein the determining the transmit power correction amount according to the selected channel quality indicator comprises:

The difference between the channel quality indicator corresponding to the fixed transmission format and the channel shield indication capable of satisfying the user's target satisfaction is taken as the transmission power correction amount.

The method according to claim 13, wherein the adjusting the transmit power by the determined transmit power correction amount comprises: using the sum of the current transmit power and the transmit power correction amount as the adjusted transmit power .

The method according to claim 1 or 8, wherein the downlink modulation mode includes a transmission format and a transmission power, the indication information of the uplink feedback includes a channel quality indicator, and the transmission format is adjusted according to a channel quality indicator. And the transmit power includes: selecting a channel quality indicator that satisfies the user target satisfaction according to the channel quality indication fed back by the terminal, and adjusting the transmission format and the transmit power according to the selected channel quality indicator.

The method according to claim 13 or 16, wherein the selecting a channel quality indicator capable of satisfying user target satisfaction according to a channel quality indication of the terminal feedback comprises:

The user target satisfaction is set in advance, and the base station sorts the channel quality indicators fed back by each terminal in descending order of values, and selects a channel whose index number is a value of the user target satisfaction and the number of all channel quality indicators. The quality indicator serves as a channel quality indicator that satisfies the user's target satisfaction.

18. A multimedia broadcast multicast service MBMS system, the system comprising: a base station and at least one terminal, wherein

The terminal is configured to receive the MBMS service from the base station, and feed back the indication information to the base station; the base station is configured to receive the indication information fed back by the terminal, adjust the downlink modulation mode according to the received indication information, and provide the terminal to the terminal according to the adjusted downlink modulation mode. Issue MBMS business.

The system according to claim 18, wherein the base station comprises: a receiving unit, a sending unit, and an adjusting unit, where

a receiving unit, configured to receive indication information fed back by the terminal, and send the received indication information to the adjustment unit;

The adjusting unit is configured to receive the indication information from the receiving unit, adjust the downlink modulation mode according to the received indication information, and send the adjusted downlink modulation mode to the sending unit;

a sending unit, configured to receive a downlink modulation mode from the adjusting unit, modulate the delivered MBMS service according to the received downlink modulation mode, and send the modulated MBMS service to the terminal _0.

The system according to claim 19, wherein the downlink modulation mode includes transmit power, and the indication information includes data reception performance,

The adjusting unit further includes: a first transmit power adjustment module, configured to determine a user actual satisfaction according to the received data receiving performance, determine a transmit power correction amount according to the actual user satisfaction, and perform the transmit power according to the transmit power correction amount. Adjustment.

The system according to claim 19 or 20, wherein the downlink modulation mode comprises a transmit power, and the indication information comprises a channel quality indicator.

The adjusting unit further includes: a second transmit power adjustment module, configured to select, according to the received channel quality indicator, a channel quality indicator that satisfies a user target satisfaction, determine a transmit power correction amount according to the selected channel quality indicator, and according to the transmit The power correction amount adjusts the transmission power.

The system according to claim 19 or 20, wherein the downlink modulation mode comprises a transmission format and a transmission power, and the indication information comprises a channel quality indicator.

The adjusting unit further includes: a modulation mode adjustment module, configured to select, according to the received channel quality indicator, a channel quality indicator that satisfies the user target satisfaction, and adjust the transmission format and the transmission power according to the selected channel quality indicator.

A base station, the base station includes: a receiving unit, a sending unit, and an adjusting unit, where

The sending unit is configured to receive the downlink modulation mode from the adjusting unit, modulate the delivered MBMS service of the multimedia broadcast multicast service according to the received downlink modulation mode, and send the modulated MBMS service to the terminal.

The base station according to claim 23, wherein the downlink modulation mode comprises Transmit power, the indication information includes data receiving performance,

The adjusting unit further includes: a first transmit power adjustment module, configured to determine a user actual satisfaction according to the received data receiving performance, determine a transmit power correction amount according to the actual user satisfaction, and adjust the transmit power according to the transmit power correction amount. Make adjustments.

The base station according to claim 23 or 24, wherein the downlink modulation mode includes transmit power, and the indication information includes a channel quality indicator.

The base station according to claim 23 or 24, wherein the downlink modulation mode includes a transmission format and a transmission power, and the indication information includes a channel quality indicator.

The adjusting unit further includes: a modulation mode adjusting module, configured to select a channel quality indicator that satisfies the user target satisfaction according to the received channel shield indication, and adjust the transmission format and the transmission power according to the selected channel quality indicator.